Are reproductive traits related to pollen limitation in plants? A case
study from a Central European meadow
Abstract
The deficiency of pollen grains for ovule fertilization can be the main
factor limiting plant reproduction and fitness. Due to ongoing global
changes, such as biodiversity loss and landscape fragmentation, a better
knowledge of the prevalence and predictability of pollen limitation is
challenging within current ecological research. In our study we used
pollen supplementation to evaluate pollen limitation (at the level of
seed number and weight) in 22 plant species growing in a wet
semi-natural meadow. We investigated the correlation between the Pollen
Limitation index (PL) and floral traits associated with plant
reproduction or pollinator foraging behaviour. We recorded significant
pollen limitation for approximately 41% of species (9 out of 22
surveyed). Seven species had a significant positive response in seed
production and two species increased in seed weight after pollen
supplementation. Considering traits, PL significantly decreased with the
number of pollinator functional groups. The relationship of PL with
other examined traits was not supported by our results. The causes of
pollen limitation may vary among species with regard to 1) different
reproductive strategies and life history, and/or 2) temporary changes in
influence of biotic and abiotic factors at a site.